Function apply

packages/angular_devkit/schematics/src/rules/base.ts:55–57

(source: Source, rules: Rule[])

 * Apply multiple rules to a source, and returns the source transformed.
 */
export function apply(source: Source, rules: Rule[]): Source {
  return (context) => callRule(chain(rules), callSource(source, context), context);
}

/**
 * Merge an input tree with the source passed in.